rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=41d/1/0x4000000000000000 softirq=128435/128436 fqs=66 (t=10500 jiffies g=251705 q=571) rcu: rcu_preempt kthread starved for 10353 jiffies! g251705 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:28952 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xb44/0x5960 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x800 kernel/rcu/tree.c:1957 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2130 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 23137 Comm: syz-executor.3 Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:hlock_class kernel/locking/lockdep.c:194 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4713 [inline] RIP: 0010:__lock_acquire+0x6bb/0x54a0 kernel/locking/lockdep.c:4965 Code: 00 00 45 3b a5 18 0a 00 00 0f 8d 99 00 00 00 49 63 c4 48 8d 04 80 49 8d 1c c6 48 8d 7b 20 48 89 fa 48 c1 ea 03 42 0f b6 14 3a <84> d2 74 09 80 fa 03 0f 8e 10 2b 00 00 0f b7 53 20 66 81 e2 ff 1f RSP: 0018:ffffc90000fd8b10 EFLAGS: 00000802 RAX: 000000000000000a RBX: ffff8880840dea70 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffff8880840dea90 RBP: 0000000000000002 R08: dffffc0000000000 R09: ffffffff8fd059e7 R10: fffffbfff1fa0b3c R11: 0000000000000000 R12: 0000000000000002 R13: ffff8880840de000 R14: ffff8880840dea20 R15: dffffc0000000000 FS: 00007f8e9f9ff700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000092ce5000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 debug_object_deactivate lib/debugobjects.c:735 [inline] debug_object_deactivate+0x101/0x300 lib/debugobjects.c:723 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate kernel/time/hrtimer.c:481 [inline] __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x3f8/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:197 Code: 01 f0 4d 89 03 e9 63 fd ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 00 <65> 8b 05 59 e1 8b 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc90018997b88 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff92003132f7c RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff8880840de000 RDI: 0000000000000003 RBP: ffffc90018997cb0 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81112d2c R11: 0000000000000000 R12: ffff8880739a0c80 R13: ffff8880739a0cb8 R14: 0000000000000000 R15: 0000000000000000 arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] kvm_xen_has_interrupt arch/x86/kvm/xen.h:42 [inline] vcpu_enter_guest+0x147c/0x4410 arch/x86/kvm/x86.c:9546 vcpu_run arch/x86/kvm/x86.c:9802 [inline] kvm_arch_vcpu_ioctl_run+0x47c/0x1b10 arch/x86/kvm/x86.c:10034 kvm_vcpu_ioctl+0x570/0xf30 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3779 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f8ea2489a39 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8e9f9ff188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8ea258cf60 RCX: 00007f8ea2489a39 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00007f8ea24e3e8f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd9af37e9f R14: 00007f8e9f9ff300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 23100 Comm: syz-executor.4 Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3880 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2599 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:write_comp_data kernel/kcov.c:218 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x17/0x70 kernel/kcov.c:284 Code: 30 f0 4c 89 54 d8 20 48 89 10 5b c3 0f 1f 80 00 00 00 00 41 89 f8 bf 03 00 00 00 4c 8b 14 24 89 f1 65 48 8b 34 25 40 f0 01 00 e4 ee ff ff 84 c0 74 4b 48 8b 86 48 15 00 00 8b b6 44 15 00 00 RSP: 0018:ffffc90018857608 EFLAGS: 00000246 RAX: 0000000000040000 RBX: ffff8880a8a10068 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffff8880796ce300 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffc90018857830 R10: ffffffff810920bd R11: 0000000000007ffb R12: ffffc90018857830 R13: 0000000000000000 R14: ffffc900188576d0 R15: ffff8880a8a100b8 __gfn_to_hva_many arch/x86/kvm/../../../virt/kvm/kvm_main.c:2144 [inline] __gfn_to_pfn_memslot+0x8d/0x420 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2437 kvm_faultin_pfn+0x171/0xbc0 arch/x86/kvm/mmu/mmu.c:3942 direct_page_fault+0xd22/0x2320 arch/x86/kvm/mmu/mmu.c:3992 kvm_mmu_do_page_fault arch/x86/kvm/mmu.h:127 [inline] kvm_mmu_page_fault+0x17e/0x17f0 arch/x86/kvm/mmu/mmu.c:5287 handle_ept_violation+0x29c/0x6e0 arch/x86/kvm/vmx/vmx.c:5325 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6038 [inline] vmx_handle_exit+0x4be/0x1950 arch/x86/kvm/vmx/vmx.c:6055 vcpu_enter_guest+0x2a90/0x4410 arch/x86/kvm/x86.c:9735 vcpu_run arch/x86/kvm/x86.c:9802 [inline] kvm_arch_vcpu_ioctl_run+0x47c/0x1b10 arch/x86/kvm/x86.c:10034 kvm_vcpu_ioctl+0x570/0xf30 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3779 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f3ad51e1a39 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3ad2757188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f3ad52e4f60 RCX: 00007f3ad51e1a39 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00007f3ad523be8f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffeae88bc8f R14: 00007f3ad2757300 R15: 0000000000022000 sched: RT throttling activated ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 45 3b a5 18 0a 00 00 cmp 0xa18(%r13),%r12d 9: 0f 8d 99 00 00 00 jge 0xa8 f: 49 63 c4 movslq %r12d,%rax 12: 48 8d 04 80 lea (%rax,%rax,4),%rax 16: 49 8d 1c c6 lea (%r14,%rax,8),%rbx 1a: 48 8d 7b 20 lea 0x20(%rbx),%rdi 1e: 48 89 fa mov %rdi,%rdx 21: 48 c1 ea 03 shr $0x3,%rdx 25: 42 0f b6 14 3a movzbl (%rdx,%r15,1),%edx * 2a: 84 d2 test %dl,%dl <-- trapping instruction 2c: 74 09 je 0x37 2e: 80 fa 03 cmp $0x3,%dl 31: 0f 8e 10 2b 00 00 jle 0x2b47 37: 0f b7 53 20 movzwl 0x20(%rbx),%edx 3b: 66 81 e2 ff 1f and $0x1fff,%dx